Art of working diamonds.



No. 67I,83|. Patented Apr. 9, I90I. E. LOESSER.

ART 0F WORKING DIAMONDS.

(Application med .my 2e, woo.)

Y (Nojlodel //v VEN Tof? l A770 EYS NITED STATES PATENT OFFICE.

ERNEST LOESSER, 0F NEW YORK, Y.

ART OF WORKING DIAMONDS.

SPECIFICATION forming part of Letters Patent No. 671,831, dated April 9, 1901.

Application iiled July 26, 1900- Serial No. 24,917. (No model.)

To all whom, t muy concern:

Beit known that I, ERNEST LoEssER, a citizen of the,United States, residing in the city of New York,borough of Manhattan,and State of New York, have invented certain new and useful Improvements in the Art of Working Diamonds, of which the following is a specilication.

For a number of centuries in the manufacturing of diamonds the workman had to resort to the tedious and slow reduction or grinding off of parts of the stone before the stone was reduced to shape for polishing, and this process of grinding down a stone is called cutting Sometimes a portion of considerable size had to be gradually ground off in this way before it was possible to produce a diamond shape or brilliant effect on the main body of the stone. The diamond-dust produced possesses some value; butit represents only a small portion of the parts removed and is not anywhere near the value of a single piece from which the equivalent quantity of dust could be produced and which piece removed would be of sufficient size to form a brilliant or which can even be fashioned into a small rose Most of the parts removed go oif into the air in the form of useless powder. In a factory which turns out a large quantity of cut and polished diamonds the loss represented by the diiference in value of the valuable dust and the equivalent fragmentary portions of the stone which could be saved without reducing them to dust amounts to considerable, and, in fact, a comparison of the values is hardly conceivable. At present there are no other processes known to the diamond manufactu rers than that of cleavage for the reduction of a stone, by which small particles of the stone are removed, and the process of grinding down the stone to produce the facets, by which a considerable quantity of dust is produced.

Prior to my invention it had never been supposed that a diamond could be cut in two by a sawing or direct cross-cutting process; but this is what is done under my present invention for the purpose of reducing diamonds to a better size for being worked up into brilliant shape, especially by removing and saving a fragment which can be fashioned into a small brilliant or rose.

My process comes into practice after that of cleaving and does away largely with both cutting and polishing My invent-ion compreheuds the method of removing a portion of a diamond while preserving the integrity of the removed portion and at the same time partly nishing a face of the stone, which consists, essentially, in starting the cut at a corner or angle of the diamond, continuing said cut through that partot` the stone in a plane at an angle to the grain or planes of cleavage of the stone, and at the same operation polishing ,both surfaces of the cut, all as particularly described hereinafter in detail and then particularly claimed.

In the accompanying drawings, Figure 1 is a side elevation of a primitive form of device adapted to saw or cut through the diamond, the same being sufficient to enable a clear understanding of the method forming the present invention. stone just above the girdle is shown as presented to the cutter. Fig. 2 is a plan view of the cutting-disk employed in my method. Fig. 3 is a transverse section thereof. Fig. 4 is a diagrammatic view showing highly magnified the graining of a diamond which has been cut through and in addition showing the relative position of the diamond to the cutter when first presented to the cutter. Fig. 5 is a diagrammatic view showing the grain of a diamond in which an arrow indicates the direction of the motion of the cutter, so as to illustrate the action of the cutter in forcing the dust toward the spaces between the layers; and Figs. 6 and 7 are detailed perspective views of the removed fragmentary portion of the stone and of the main body of the stone, which has been cut or sawed through and its cut surface polished.

In this view a corner of aV Similar letters of reference indicate corre- IOO sawing one. The cutteris made of a metal,

such as-phosphorbronze, which is of lowv In my copending application, Serial No.

715,304, filed May 2, 1899, a machine is de-l scribed in detail in which a cutting-disk is shown and which enables the carrying out of the method forming the subject of the present invention. The cutting-disk of the present invention differs slightly from that disclosed in said application in that there are a numberof very small diainond-gritsembedded in the edge and sides of the cutter, and these are indicated by the letter b. The object of these will appear hereinafter. All diamonds are generally formed regularlyin the form of octahedrons or rhonibic decahedrons,in which each of the sides has a distinct grain of its own, which is not parallel with the grain of any other side except the opposite parallel side. 'Ihis enables what is known as cleav.- ing; butin order to produce the facets, table, or cullet culasse on astone it is necessary to polish against the grain, for a diamond cannot be polished except against the grain. Hence to do this the facets must be cut at a slight angle, at least, to the grain, while the table and cullet are cut at a greater angle to .the grain. This necessitates the removal of a considerable portion of the stone,and therefore .a great reduction in the value of the parts removed.

In the present invention (see particularly Figs. l and 4) a corner of a stone S is held up to the edge of the cutter B, so that the plane of the cutter will be in the plane of the surface which is to be produced thereby.

It has been found practically impossible to cut or saw directly through the thicker portion of the stone, even with a metallic cutter having a low heat-retaining quality. When a cutter of this quality, however, is revolved at a very high rate of speed and one corner of the stone presented to the cutter, the latter will pass clear through the stone and without destroying its integrity cut or saw o the fragment which heretofore, in order to pro*- duce the fiat table formed by the cross-cut, had to be gradually and very slowly ground down, producing powder which flies into the air and is of no commercial value.

Referring to Fig. 4, it will be seen that the side S of the stone has a grain which lies in planes extending substantially in the direction of motion of the cutter B, so that the grain parallel wi'th that side of' the stone oers slight resistance to the cutter, while the grain atthe side S2 of the corner which is being cut lies in planes which aredirected toward the directionfof the motion of the cutter B. This disposition of the grain at S2 greatly facilitates the polishing of the stone, because theAdiamond-dust'which is produced is directed toward the edges of the layers at S2 and the dust has a tendency to be detained in the spaces which exist between the edges, and thereby a polishing of the surface which is being cnt or sawed off is produced. The farther the cutter cuts through the stone the hotter the stone becomes, thus acting to expand the grain of the stone and causing the particles of stone-that is to say, the diainond-dust-toact on the edges of the grain more rapidly,so that the throu gh-and-throu gh cutting is facilitated.

It should be understood that the diamondgrits b in the edge and sides of the cutter facilitate the clearance of the cutter through the stone, inasmuch as the said grits project slightly from the opposite surfaces of the cutter, so that they take the place of the set of the ordinary saw. Without this the cutter could not pass through the stone.

In Fig. 5 the grain. of the stone is shown enlarged for the purpose of illustrating the manner in which the polishing takes place by means of the cutter, which moves toward the edges of the grain. The polishing produced by the action of the cutter does away to -a great extent with the usual polishing which is done by the lap or polishing disk.

After severing the stone the parts are worked up in the usual manner for producing brilliants or other styles.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

- l'. The method of removing a' portion of a diamond While preserving theintegri'ty of the removed portion, and at the same time partly finishing a face of the stone, which consists essentially in starting the cut at a corner or angle of the diamond, continuing said cut through that part of the stone, in a plane at an angle to the grain or planes of cleavage of the stone, and at the same operation polishing both surfaces of the cut.

2. The method of removing a portion of a diamond while preserving the integrity of the removed portion, and at the same time partly Iinishing a face of the stone, which consists essentially in starting the cut at a corner or angle of the diamond, continuing said cut through that part of the stone, in a plane at an angle to the grain or planes of cleavage of the stone, whereby the same is heated and the grain expanded, and at the same operation polishing both surfaces of the cut by the working of the diamond-dust against the edges of the grain.

In testimony that I claim the foregoing as my invention I have signed my name in presence'of two subscribing witnesses.

' ERNEST LOESSER.

Witnesses:

PAUL GOEPEL, GEO. L. WHEELOCK.

IOO

IIO 

